1. Technical Field
The invention relates to an improved process for the preparation of macrocyclic compounds useful as agents for the treatment of hepatitis C viral (HCV) infections.
2. Background Information
The macrocyclic compounds of the following formula (I) and methods for their preparation are known from: Tsantrizos et al., U.S. Pat. No. 6,608,027 B1; Llinas Brunet et al, U.S. Application Publication No. 2003/0224977 A1; Llinas Brunet et al, WO 2004/037855 Llinas Brunet et al, U.S. application Ser. No. 10/945,518, filed Sep. 20, 2004; Brandenburg et al., WO 2004/092203 and Samstag et al., U.S. Application Publication No. 2004/0248779 A1:
wherein Q is a substituent of the following formula:
and the other variables are as defined herein.
The compounds of formula (I) are disclosed in the above-mentioned patent documents as being active agents for the treatment of hepatitis C virus (HCV) infections. The methods disclosed for the preparation of these compounds include many synthetic steps, which may involve protection and deprotection of certain reactive groups. The problem addressed by the present invention is to provide a process which allows for the manufacture of these compounds with a minimum number of steps on a technical scale with sufficient overall yield.